Liver Extracellular Matrices Bioactivated Hepatic Spheroids as a Model System for Drug Hepatotoxicity Evaluations

Abstract

Drug‐induced liver injury (DILI) is a leading cause of acute liver failure. A major obstacle in the prediction or evaluation of DILI is the lack of an experimental model(s) that recapitulates the stable and physiologically relevant liver functions and reflects accurately the level of drug hepatotoxicity. Native extracellular matrices that are secreted and maintained by resident cells are receiving great interest as biomaterials for cell culture and cell delivery. In this study, a hepatic spheroid model system, treated with cryopulverized liver biomatrix scaffolds (LBSs), is established for DILI investigations. The LBSs provide a liver‐specific microenvironment bioactivating metabolic traits paralleling those in vivo, resulting in the fact that LBS‐bioactivated model system shows enhancing liver‐specific functions (albumin secretion, urea synthesis, glycogen storage), cytochrome P450 enzymes (CYPs) metabolic activity, bile excretion, and increased expression of phase I and II metabolism enzymes, transporters, and nuclear receptors, collectively hypothesized to result from increased cell–cell and cell–matrix interactions. Toxicity assessments with LBS‐bioactivated hepatic spheroids reveal an improved sensitivity in identifying hepatotoxic compounds. In summary, using this model system, a simple but robust high‐throughput‐compatible methodology is developed, which shows great potential for use in toxicity screening assays, and represents an alternative to animal models for studying DILI.

Comprehensive Evaluation of Organotypic and Microphysiological Liver Models for Prediction of Drug-Induced Liver Injury

“…Liu et al established HepaRG spheroids using decellularized rat liver as scaffold. They showed that this liver biomatrix scaffold enhances expression of phase I and phase II enzymes, drug transporters, and nuclear receptors for up to 28 days compared to scaffold-free spheroid culture (Liu et al, 2018). However, expression levels of most genes were still considerably lower than in PHH.…”

Organotypic and Microphysiological Human Tissue Models for Drug Discovery and Development—Current State-of-the-Art and Future Perspectives

“…Although these polymers are biocompatible and provide defined chemical composition as well as tunable mechanical properties, they do not resemble the native biochemical microenvironment of the human liver. To overcome these limitations, human liver cell spheroids have been cultured on decellularized rat liver scaffolds, resulting in increased expression of phase I, phase II enzymes as well as drug transporters in HepaRG cells for up to 28 days (Liu et al, 2018a). Although these scaffolds provide a more relevant ECM than alginate or synthetic polymers, they are difficult to obtain from human sources, are not chemically characterized, and have substantial batch-to-batch variability.…”

3D human liver spheroids for translational pharmacology and toxicology

“…HepaRG cells are generally considered to more closely resemble human hepatocytes than HepG2 cells on both transcriptomic and functional level particularly related to expression of drug‐metabolizing enzymes and drug transporters 40,41 . Phenotypes of HepaRG spheroids could be further improved by culture in liver biomatrix scaffolds generated from decellularized native rat livers 42 . Recent studies used both HepG2 and HepaRG spheroids for detection of genotoxicity using the Comet assay, an electrophoretic measurement for the detection of DNA strand breaks in single cells 43,44 .…”